Oil still



Jan. 5 1926. Y

J. PRIMRosE OIL STILL Filed July 2, 1921 nvszntoz y*Patented Jan. 5, l9 26'.,'

, UNITED STATES? PATENT OFFICE. A

I Joan rnnmosn, or N liw Yoan,V N. Y., A ssIeNoR To Pownn srncIAL'rYcoMrANY, or-

. Naw Yoan,l N. Y., A conronarron or; NEW-Yoan.

^ OILv STILL.

Application lcd July 2,`

- l To all whom t `may concern; Be it known that I, JOHN PRIMRosn, a

citizen of the United States of America, residing at.New nYork, in the county and State of New York, have inventedcertain new and usefullniprovements in Oil Stills,

of which the following is a full, clear,and

exact description.

" In certain forms of cracking still nowl well known and largely used, it is'usual to build the furnace with a dividing partition or wall of yrefractory material between the fire chamber and the bank of tubes through which the oil flows.` The .hot gases of comtion is designed forjuse.

- high rate, itjdid notcarry oi the heat absorbed ata rate which would keepthe. temperature of the metal of the heating surface' bustion in such cases pass from the fire .chamber over the bridge wall and' sweep down over the oil tubes on their way to the flue. This is a general description of a typical form. of still, `but for purposes of the present application it will suilice to indicate the general form of apparatus to. Vwhich the inventionsubject of thls applica- 'In stills of.y this character )it has been found necessary tomaintain a relatively low furnace temperature; for exam le about 1400, for obtaining the best resu ts in distillation',1but .this involves the use of a largeexcess vplume of air,- and in consequence a somewhat low 'fuel economy. Efforts to cut .downthe amountof fuel and to raise thefurnacetelnperature have not been satisfactoryyasin such event the top 'row of oil became overheated,because although the' oil was passing-through them at a very below the burning point( It also resulted in a violent heating ofjthe oil at this point,

bringing about a deposit of carbon onthe` inside of the tubes too great to permit of long continued operation. r f

A careful 4study of these facts and. conditions, led t me to "believe.- that' the main ob'- stacle to the economicaluse of this type of still lay in theffact that the refractory roof {wallof the furnace' became very highly 'radiant heatwas the feature, 'which' opera heated and radiated this heat directly upon the` upper row of soiltubes, :and .that this ted-as aninsuf bleobstaz1e tothe 'emcient operation o -sucl long as it was Present -Iih'refemmtiaht w .mojve its cause and consequently 'teeca 1921. sei-iai No. 482,135.

and having once succeeded in doing this I found that a great gain in economy and efficiency .was at 'oncesecured This invention therefore resides primarily in eliminating to as great a vdegree as 1s practicable and possible, the Aeffect upon the oil. tubes of a still, of'direct radiant heat,

whereby the heating will be accomplished by convection, and the most feasible means that I have devised for accomplishing this is -to establish as far as 'practicable opposing heating or heat absorbing surfaces instead of` a heat radiating and a heat absorbing surface.

Y Forthis purpose I construct the furnace vin the usualimanner with a re chamber and 4a tube containing chamber into which the hot Agases iow after passing over the top of the bridge wall. The roof of the. fire chamber may be of refractory brick, but that of the other chamber immediately above the bank of tubes iscomposed chieiy of oil directlyA from the roof onto, the bank of tubes, that a very great advantage isgained. Of course heat will be radiatedto some extent from the side walls of the tube cham?.

ber` but this radiates at an angle to the tubes and not directly upon much less serious. cause, the direct radiation of heat from the roof, is practically eliminated.

* Thenature and principle of ythis invention' aresuch asto make it of much wider application than to the mere protection of the tubes of an oil still. For example, the same plan is of great value and importance in the case` ezt-any kind of fluid heater in 'ble of carrying of theheat as rapidly -as the heating surface absorbs it by radiation.

applies, for example, to independently them, and its effect is- The main disturbing fired superheaters, or to gas heaters, or to other like devices in which the heating surface absorbs the heat direct from the fulinace. It is, of course, a matter of common knowledge that the heat i's absorbed by radiation at a much higher rate than by convection.

I have illustrated my improvement in the accompanying drawing as applied to an o1l still, the said drawing being a vertical sectional view of any ordinary form of still having the general characteristics hereinbefore described.

The furnace walls 1 are of the usual character and material, and a bridge wall 2 is built up to divide the furnace into two chambers communicating over the top of the said wall. The source of heat may be a coal lire or fuel oil.

The roof of the fire chamber is com osed partly or wholly of refractory bloc s 3, through which pass oil tubes 4 placed at a suitable distance apart. The roof of the tube chamber is composed of exposed tubes 4, and these also are placed as close together as structural conditions will permit.

Below in the tube chamber is arranged a bank of tubes 5 connected in any suitable manner, but preferably so that the flow of oil will be counter to the flow of hot gases. The roof tubes 4 are connected in series with those of the bank 5, and all tubes 5 erposedl to the hot gases are preferably of steel encased in corrugated rlngs of cast iron. The portion of the roof tubes 4 directly over and opposing the tube bank 5 are preferably provided with plain cast iron coverings or casings 7. Such coverings are not essential as bare tubes may be used as well.

Beneath the bank of tubes is a damper 6, and otherwise the apparatus is supplied with the usual and well known accessories.

If the roof of the tube chamber were of some refractory material it would become highly heated and radiate its heat directl;y upon the upper row of tubes of the bank 5. and this, as pointed out above, will .result in overheating the top row of tubes. As constructed, however, the roof of the tube chamber absorbs rather than radiates heat, in the same way -as the upper row of tubes of the bank by contact with the hot. gases only. Hence. as the opposing heating surfaces are at substantially the same temperature, there is no appreciable interchange of heat between them by radiation.

The so-called bridge wall 2 protects the tubes 5 from the direct radiant heat of the fire chamber of the furnace. The hot gases of combustion are directed from the furnace directly between thetwo banksof heating surfaces -4 and 5. -Under these conditions the upper row of tubes in bank 5 are exposed to the hottest gases and would tend to become highly heated. If the opposed heating surfaces 4 were omitted the opposing wall in opposition to the surfaces 5 would become highly radiant and this radiant heat would act cumulatively with the heat of convection of the hot gases upon the uppermost tube row in 5 and these upper tubes would be over-heated thereby overheating the oil therein and necessitating frequent tube replacements. By providing the opposed heating surface 4, I not only prevent radiation from hot brickwork but also prevent interchange of heat by radiation between the heating surfaces 4 and 5. there is a useful recovery of the heat in the oil passing through the pipes 4. In effect, the upper heating surface provides a so-called dark spot in opposition to the heating surfaces 5.

In heaters it is desirable that the heat absorbing surfaces should be so disposed with relation to source of heat that every unit area of the surface should absorb heat' tures are secured furt er on in the heater thereby causing a higher heat absorption at such points.

This construction has been found to completely eliminate the objection to stills and other devices of this general character and type, andy permits a much higher furnace temperature without injury to the oil, steam or other similar tubes.

The method of treating oil by the apparau tus herein claimed is not claimed in the present application but is claimed in my copending application, Serial No. 611,932, filed January 11, 1923.

What I claim as my invention is:

1. An oil heater comprising a lire chamber in which intense radiant heat is developed and a tube chamber, a heat absorbmg surface in said tube chamber, an intermediate refractory wall between the tube chamber and the fire chamber and a roof for the tube chamber composed of heat absorbing surfaces disposed in opposition to the heat absorbing surface in the tube chamber whereby the ast mentioned heat absorbing surfaces are protected against overheating by radiant heat.

2. An oil still comprising a furnace divided by a bridge wall into two compartmeritsy communicating over the top of saidl wall, one compartment being a fire chamber in which the heat of combustion develops intense radiant heat, a bank of tubes in the other chamber, a roof for the fire chamber Furthermore diating material, whereby the exposed row of tubes in said bank will be protected from the direct radiation of posing wall.

4. In an apparatus ofthel kind herein described, 'the combination with a furnace in which intense radiant heat is developed, of a heat absorbing surface screened from the tire and divided into two, opposing parts between which the heat of the furnace-is directed, whereby no part of said heat absorbing surface will be exposed to Vdirect "heat rays from the fire or the furnace walls.

5. In a furnace. a combustion chamberin o which intense radiant heat is developed, a

heat absorption chamber in open communication therewith, fluid conveying means located in said heat absorption-chamber, said heat absorption chamber having wall portions in `radiant heat receiving relation relative to said combustion chamber and in heat radiating -relation to said Huid conveying means, and means upon said wall to prevent such heat radiation.

6. An oil heating apparatus comprising in combination, means includin a plurality .of conduits through which the 011` to be heated is passed, meansV includinga high intensity source of heat for subjecting said conduits to heat of convection, and means for preventing the destruction of the said conduits and the overheating of the oil thereinby excessive radiant heat, said means comprising a heat-absorbing means interposed ata point out of the stream'of hot gases and cooperating with the aforesaid conduits to prevent a radiant heat interchange therewith.

7. An oil heating apparatus comprising in combination, with means including a lurality of conduits through which the oi to be heated is passed, means includin a hi h intensity source of heat for subjecting said conduits to heat of convection and means for preventing destruction of said conduits and the overheating of the oil therein by excessive radiant heat, said means including a non-radiant opposing surface located out of the stream o for protecting such of the aforesaid conduits whichwould otherwisebe subjectto destructive radiant heat.

8. An oil heating apparatus comprising i means .v including a plurality of conduits heat from said opot gases from said source through which the oil is passed, means such as a high intensity source of heat for subjecting the oil in said conduits to heat of conyection, means for protecting the oil in such of the conduits ,as would otherwise be Vexposed to destructive radiant heat and for usefully' recovering heat from said source, said means including oil-containing heatabsorbing conduits in position to provide a relatively dark area in opposition to the aforesaid exposed conduits.

9. An oil heating apparatus comprising in combination with a plurality of conduits for the oil to be heated, means including a high intensity source of .Y heat for heating oil in said conduits, and means for protecting such of the conduits and the oil contained tbereineagainstdestruction and for usefully recovering heat from said source,

said means. including oil-containing heatabsorbing conduits positioned to provide a relatively dark area in opposition to such of the aforesaid conduits which would otherwise be subject to radiation.

10. In an apparatus of the kind described, a bank of tubes adapted to be swept by hot gases from a source developing intense radi-4 ant heat, 'an opposing wall'therefor of heatabsorbing surface as c distinguished from' heatradiating material, 'whereb the exposed ro'w of tubes in said bank wlll be protected from direct radiation of heat from said opposing wall, means for conveying a medium to be heated first through the bank of tubes to' impart an initial heating thereto, and thence through the last mentioned heatabsorbing surface to further heat the same.

n 11.. In .a device of the class described, in combmatlon, a furnace `having a re chamber in which intense radiant heat is developed and a heat-absorption chamber, a heata sorbmg surface therein adapted to receive heat from .the hot gases and heat up a medium conveyed therethrough, means for shielding portions of said surface from the direct heat of the fire chamber, and means for controlling and preventing an excessive heating of said surface by radiation from the chamber walls including a second-heaty absorbing surface in opposition to and co.-

operating with the first mentioned heating "surface to prevent either surface attaining the kind described,

an excessive temperature. 12. In an apparatus of the combination with a furnace in which intense radiant heat is developed, of a heatvabsor tion `chamber therein, of a heatabsor ing surface within said chamber, a

second heat-absorbing surface disposed in `13 lin anl apparatus ofthe kind described,

in combination, a heat-absorption chamber.

and a refchamberin which intense radiant' heat is developed,'wal1s for said chambers, a heat-absorbing surface in; the absorption chamber adapted to be swept by hot gases, a second heat-absorbing surface on the wall opposite the first heat-absorbing surface and adapted, by the absorption of heat thereby to prevent destructive radiation upon the first mentioned heating surface from said opposite wall, and means for directing gases from thel lire chamber between the two heatabsorbing surfaces and for shielding other portions of the first heat-absorbing surface' from the direct heat' of the'fire. V v

14. In an apparatus of the kind described, in combination, a source of heat adapted to develop intense radiant heat, means includarranged to shield one of said surfaces from the direct heat of said source and to direct the hot gases from the source between the said surfaces.

15. In an apparatus of the kind described,

a furnacein which intense radiant heat is developed, in combination with. a plurality .of banks of heating surfaces through which the medium to be heated flows, a wall screening one bank ofheating surfaces from the direct radiant heat ofthe furnace chamber,

but permitting hot gasesto-sweepsaid last mentioned bank,.the othery bank of heating surfaces being disposed in opposition to the lscreened surface to absorb heat and prevent radiation of heat to those surfaces ofl such screened surface which are exposed to the p hottest furnace gases, whereby the gas temperatures may be increased and the heating surfaces of the screened surface subse uently traversed by the hot gases may absor proportionally more heat.V

In testimony whereof 1 hereto-[afix my i signature.

' JOHN iennsmosnl 

